直驅式軸向磁通電動輔助自行車馬達最佳設計分析

Optimal Design of Direct Drive Axial Flux Electric-Auxiliary Bicycle Motor

丁富軒(Fu-Xuan Ding)

指導教授 ： 陽毅平

國立臺灣大學/工學院/機械工程學研究所/碩士(2013年)

https://doi.org/10.6342/NTU.2013.02115

摘要

本研究針對用於助動式腳踏車的軸向磁通同步永磁馬達規劃了一套系統性的多目標設計方法，在最佳化的設計過程中，為了達到所有的行車需求，以特定的轉矩轉速曲線做為設計目標，在特定的驅動控制條件下計算出其曲線所對應的反電動勢因數以及電阻值，並以其作為基準計算馬達各部位之尺寸大小。在馬達磁場的分析中，利用分環法(Quasi-3D)將馬達磁場建立成數值模型進行分析，在每個環狀平面裡，利用一維的無槽型馬達氣隙磁通解析解搭配等效磁路模型以及有效氣隙分布函數修正槽效應與氣隙漏磁等現象，求得馬達的氣隙磁通密度分布函數，並進一步得到馬達的各參數值。在最佳尺寸尋找的過程中，利用妥協規劃法(Compromise Programming)來評鑑各尺寸組合在綜合了體積、重量以及效率表現上優劣與否的指標，在眾多尺寸組合中權衡出一組馬達尺寸組合在各目標上最為符合需求的最佳解。
　　在最後利用三維的有限元素分析模型驗證其準確性，並確保馬達符合最初的設計需求，驗證了利用本研究所規劃的性統性設計方法，可找出一組用於助動式腳踏車的馬達的最佳設計尺寸，其尺寸滿足行車所需的條件，並且在體積、重量、效率的綜合表現上是所有尺寸組合中最佳的一組。

關鍵字

軸向磁通永磁馬達 ； 電動自行車 ； 多目標最佳設計 ； 氣隙模型 ； 有限元素分析

並列摘要

This thesis proposes a systematic process of a multi-objective optimal design of an axial-flux permanent-magnet synchronous motor (AFPMSM) for electric-auxiliary bicycles. The optimal design process uses a Quasi-3D analytical model of the magnetic field in an AFPMSM to calculate motor sizes under the same back-EMF factor target and phase resistance limit to achieve the specific motor torque-speed curve requirement. This model is derived from a one-dimensional analytical solution of the slotless air-gap flux density distribution and equivalent magnetic circuit model with an effective air-gap permeance distribution function to correct the flux distribution with the slot effect and flux leakage. In the search of the optimum motor sizes, the Compromise Programming is used to assess the set of motor parameters and make the performance indices, such as volume, mass, and efficiency, closest to all its best valuation on aggregate. The 3-dimensioanl finite element method (FEM) verifies and refines the final design, demonstrating that the proposed design process develops an axial-flux permanent-magnet motor with a high torque density for electric-auxiliary bicycles.

並列關鍵字

Axial-flux permanent-magnet motor ； electric bicycle ； multi-objective optimal design ； air-gap model ； finite element analysis

參考文獻

[58] 丁奕元, 基於霍爾感測器之改良型轉子角度估算法應用於內藏式永磁同步馬達之驅動控制, 碩士論文, 國立台灣大學, 2011.

[2] G. Rose, "E-bikes and Urban Transportation: Emerging Issues and Unresolved Questions," Transportation, vol. 39, no. 1, pp. 81-96, Jan. 2012.

[4] W. Chlebosz, G. Ombach, and J. Junak. "Comparison of Permanent Magnet Brushless Motor with Outer and Inner Rotor Used in E-bike," in XIX International Conference on Electrical Machines (ICEM), Rome, Italy, 2010, pp. 1-5.

[8] K. Sitapati and R. Krishnan, "Performance Comparisons of Radial and Axial Field, Permanent-Magnet, Brushless Machines," IEEE Transactions on Industry Applications, vol. 37, no. 5, pp. 1219-1226, Sep./Oct. 2001.

[9] A. Cavagnino, M. Lazzari, F. Profumo, and A. Tenconi, "A Comparison between the Axial Flux and the Radial Flux Structures for PM Synchronous Motors," IEEE Transactions on Industry Applications, vol. 38, no. 6, pp. 1517-1524, Nov./Dec. 2002.